#include <iostream>
using namespace std;

int main()
{
    int n;
    char c;
    cin>>n;
    int r=n % 123;
    if (r>=97 && r<=122) c=(char)r;
    else
    {
        r = n % 91;
        if (r>=65 && r<=90) c=(char)r;
        else c = '*';
        
    }
    cout<<c<<endl;
    return 0;
}

